Hierarchical data storage processing apparatus for partitioning resource across the storage hierarchy

ABSTRACT

The present invention relates to a data storage processing apparatus and the object of the present invention is to provide storages including off-line media and to improve the usability of users as well as removing the unfairness among users. The resource of data storage processing will be divided and dynamically allocated and simultaneously various multiple storages in the resource of the data storage processing will be integrated in accordance with file systems and hierarchically arranged according to speeds and features, and file systems will be constructed on that hierarchical various multiple storages, and thus, users are able to access to the optional files making no distinction of various multiple storages and/or file system.

TECHNICAL FIELD

The present invention relates to a data storage processing apparatus andis suitably applied to the network storage server based on theclient/server model.

BACKGROUND ART

Heretofore, as a data storage processing device (network storage server)based on the client/server model to be commonly used by a plurality ofusers via network, there has been a network file system server whichconnects a juke box having a built-in magnetic disc and amagneto-optical disc to a workstation and loaded with a device driver, aunique file system and a management software of the file device on apart of its operating system on the workstation.

This network file system server uses a software which makes the computerstorage/file server connected to the network usable as if it were itsown computer storage via the network. More specifically, it mounts thestorage of the other computer in the directory on its computer via thenetwork. By means of this network file system server the user canconnect the network storage having large capacity to his own computervia the network and can utilize it.

The special features of this network file system (NFS) server arefirstly, bit cost decreases by connecting the juke box through makinguse of high speed of the magnetic disc file server, secondly, allremovable storage media in the juke box are controlled as one volume.This means that the system controls the volume of removable media as anextended space of the magnetic disc and the user cannot use individualremovable media freely.

Thirdly, the network file system server has adopted the file systemwhich treats the juke box as a part of the magnetic disc and the serverdeals with only one file system. Fourthly, by conducting automatic filemigration between storage hierarchy of the magnetic disc and the jukebox, access speed approaches to the magnetic disc. Also by physicallyconnecting a plurality of juke boxes, "infinite " to infinitely largecapacity file. Lastly, its management target is only on-line storage anddoes not exchange media during the system working condition, nor does itperform off-line media management.

Thus, the network file system server has the storage construction ofwhich semiconductor memory, magnetic disc, optical disc andmagneto-optical disc are hierarchized according to the access speed, andcontrols resources which the server has by means of hierarchical storagemanagement.

However, since the hierarchization according to access speed isconducted in the NFS server, the device which brings the access turnaround time closer to the access time of high speed storage such as themagnetic disc, has been derived. However, since the on-line storagecapacity management for each client has not been conducted, it hascreated a problem that unfairness occurs among clients concerning theon-line capacity of storage which the client has. Here, the clientindicates the client in the client/server model.

Furthermore, since the hierarchical management has been conducted onlyfor the on-line storage, it has created a problem that the storage mediacannot be exchanged during the system working condition when usingstorage having removable storage media which allows the magneto-opticaldisc to be removed. This means that the media containing users' filescannot be accessed at all after the system starts operating.

Moreover, there are various file systems corresponding to the quality ofdata and characteristics of storages at the present. However, since thehierarchical storages are treated as one large volume, it is a problemthat only one file system can exist in the system. This means thatusers' files and data which are constructed by the file systemunsupported by the system cannot be accessed.

Furthermore, there is a tendency that each client's file and dataincrease in the on-line storage. On the other hand, since files havinglow access frequency and files which are no longer accessed are held inthe on-line storage, the usability of on-line storage decreases. Also,since the removable media are entirely controlled by the system, it hascreated a problem that the client cannot independently handle theremovable storage media which he has in the system.

The present invention has been done considering the above points and isproposing a data storage processing apparatus which is capable ofimproving the usability of the user as well as removing the unfairnessamong users.

DISCLOSURE OF INVENTION

To obviate such problems according to the present invention, resourcesof the data storage processing (2, 3, 4, 5, 6, 7, 8, 9) is divided anddynamically allocated to users, various multiple storages (2, 6, 7, 14)comprising storage resources in the data storage processing resources(2-9) is integrated by the file system and hierarchized according tospeeds and features, and the file system is constructed on variousmultiple storages hierarchized (2, 6, 7, 14) and users can access theoptional files without making distinction between various multiplestorages (2, 6, 7, 14) and/or file systems.

As well as dividing and dynamically allocating resources (2-9), variousmultiple storages (2, 6, 7, 14) is integrated by the file system andhierarchized according to the speed and characteristics, and since thefile systems are constructed on hierarchical various multiple storages(2, 6, 7, 14) and users are able to access to the optional files makingno distinction of various multiple storages (2, 6, 7, 14) and/or filesystems, the usability of the user is improved and unfairness amongusers is removed.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram showing the general construction of a datastorage processing apparatus according to one embodiment of the presentinvention.

FIG. 2 is a block diagram showing the construction of the data storageprocessing apparatus.

FIG. 3 is a linear diagram illustrating the division of resources in thedata storage processing apparatus.

FIG. 4 is a linear diagram illustrating the software management moduleof the divided resources in the data storage processing apparatus.

FIG. 5 is a linear diagram illustrating the integration of variousmultiple file systems in the data storage processing apparatus.

FIG. 6 is a linear diagram illustrating the off-line file management inthe data storage processing apparatus.

FIG. 7 is a linear diagram illustrating the on-line and off-line storagemedia management in the data storage processing apparatus.

FIG. 8 is a block diagram showing the automatic labeling system in thedata storage processing apparatus.

FIG. 9 is a linear diagram illustrating the automatic adjustment of theon-line capacity in the data storage processing apparatus.

FIG. 10 is a linear diagram illustrating various multiple file systemsin general according to the other embodiment of the present invention.

FIG. 11 is a block diagram illustrating the file staging in the datastorage processing apparatus.

FIG. 12 is a linear diagram illustrating the slot management ofremovable storage in the data storage processing apparatus.

FIG. 13 is a flow chart showing the data storage processing procedure inthe data storage processing apparatus.

FIG. 14 is a flow chart showing the garden manager forming processingprocedure of FIG. 13.

FIG. 15 is a linear diagram showing a path map table to be formed inFIG. 14.

FIG. 16 is a flow chart showing the storage manager forming processingprocedure of FIG. 14.

FIG. 17 is a flow chart showing the mount processing procedure of FIG.16.

FIG. 18 is a flow chart showing the read/write access processingprocedure of FIG. 16.

FIG. 19 is a flow chart showing the cache check processing procedure ofFIG. 18.

FIG. 20 is a linear diagram showing the cache data management list to beused in FIG. 19.

FIG. 21 is a flow chart showing the garden file system (GFS) processingprocedure of FIG. 18.

FIG. 22 is a flow chart showing the media manager forming processingprocedure of FIG. 21.

FIG. 23 is a flow chart showing the off-line processing procedure ofFIG. 22.

FIG. 24 is a linear diagram showing the intra-media management table ofFIG. 23.

FIG. 25 is a flow chart showing the read cache processing procedure ofFIG. 22.

FIG. 26 is a diagram showing the media access management table to beused in FIG. 19 and FIG. 25.

FIG. 27 is a flow chart showing the write cache processing procedure ofFIG. 22.

FIG. 28 is a flow chart showing the actual write processing procedure ofFIG. 27.

FIG. 29 is a flow chart showing the media discharging processingprocedure of FIG. 28.

FIG. 30 is a flow chart showing the other file system processingprocedure of FIG. 18.

BEST MODE FOR CARRYING OUT THE INVENTION

Referring to the drawings, one embodiment of the present invention willbe hereinafter described in detail.

(1) General Construction of Data Storage Processing Apparatus

FIG. 1 generally shows a data storage processing apparatus 1. As thefirst storage, this data storage processing apparatus 1 has an autochanger 2 which stores the first storage media, i.e., magneto-opticaldisc into the magneto-optical disc memory 2B in order that it can beremoved from the outside by the loading/unloading device 2A, and as thesecond and the third storages, it possesses a hard disc memory 3 and asemiconductor memory 4 having the second and third storage media, i.e.,a hard disk and a semiconductor random access memory (RAM), and it isable to conduct the write processing or read processing of data in thestorage area of the magneto-optical disc, the hard disc and thesemiconductor memory element according to softwares, such as theoperating system and management software stored in the internal memory 6by the central processing unit 5 (CPU). As the auto changer 2, a devicesuch as a juke box can be applied.

At this point, as shown in FIG. 2, the data storage processing apparatus1 controls various kinds of storages, such as the semiconductor memory4, the hard disc memory 3 and the magneto-optical disc memory 2, theaccess time of which during write processing and read processinggradually increases in the respective order, as one storage 7 as a wholevia bus 6.

Thus, the CPU 5, by connecting the data to be written in or read fromthe storage 7 to the network 9 of such as Ethernet, FDDI (fiberdistributed data interface) via the network interface 8, connects theclients connected to the network 9, i.e., computer file system includingpersonal computer client 10 and 11 and workstation client 12 as the NFS(Network File System) and transmits and receives the data.

The data storage processing apparatus 1, after storing the data fromclients of the file system in the magneto-optical disc memory 2B whichis the first storage media, by the auto changer 2, outputs the storedmagneto-optical disc Dmo by the loading/unloading device 2A and storedin the external storage by the operator, and thus, the data can bestores externally.

At the time when the magneto-optical disc Dmo is outputted from theloading/unloading device 2A, the CPU 5 prints the access informationallocated to the outputted magneto-optical disc Dmo on the label Lbl bylabel printer 12 and supplies it to the operator for the operator topost the label Lbl supplied on the outputted magneto-optical disc Dmoand to store it.

As a result, when the data storage processing apparatus 1 receives theaccess information from clients 10, 11 and 12 for the data memorized inthe magneto-optical disc Dmo which is stored in the external storage, itinforms the operator the access information so that the operator easilyfinds the corresponding magneto-optical disc Dmo and is able to installit to the loading/unloading device 2A of the auto changer 2.

(2) Storage Resources Management

The CPU 5 and the network interface 8, the semiconductor memory 4, thehard disc memory 3 and the magneto-optical disc mounted to the slot ofthe auto changer 2 in the storage 7 are resources of the data storageprocessing apparatus 1 and as shown in FIG. 3, divided by the dividinglines La, Lb and Lc as a plurality of resource working sets, and isdynamically allocated (i.e., in order that they can be changed as thetime proceeds) to the software which manages the divided resourceworking sets (hereinafter referred to as garden).

More specifically, storage capacities of the semiconductor memory 4, thehard disc memory 3 and the magneto-optical disc memory 2B are divided bythe partition lines La, Lb and Lc respectively, and thus, thesemiconductor memory 4 is cut out into four (4) memory areas AR11-AR14,and in the similar manner, the hard disc memory 3 is divided into four(4) memory areas AR21-AR24 and, moreover, the magneto-optical discmemory 2B is divided into four (4) memory areas AR31-AR34.

Then, the working sets of cut out resources are dynamically managed bythe corresponding software management module respectively as shown inFIG. 4. In FIG. 4, the server manager SVM is a module for managing theoverall resources of the data storage processing apparatus 1, forming aplurality of gardens GDN1-GDN3 for managing the divided working sets ofdivided resources, and dynamically allocates resources of the datastorage processing apparatus 1 upon dividing in gardens GDN1, GDN2 . . .GDNk as the working sets of resources.

In this connection, in the case of the embodiment of FIG. 3, memoryareas AR11, AR21 and AR31 of the semiconductor memory 4, the hard discmemory 3 and the magneto-optical disc memory 2B are allocated to thefirst garden GDN1. Also, memory areas AR12, AR22 and AR32 of thesemiconductor memory 4, the hard disc memory 3 and the magneto-opticaldisc memory 2B are allocated to the second garden GDN2 and memory areasAR1K, AR2K and AR3K of the semiconductor memory 4, the hard disc memory3 and the magneto-optical disc memory 2B are allocated to the kth gardenGDNK.

The gardens GDN1, GDN2, . . . GDNK are constructed by a garden managerGDM, a storage manager SGM and media managers MDM1, MDM2 . . .respectively. One garden manager GDM and one storage manager SGM existin each garden GDN and media managers MDM1, MDM2 . . . exist in eachslot obtained as working sets of resources in the magneto-optical discmemory 2B of the auto changer 2.

Accordingly, the relation between the working sets of divided resourcesand allocated gardens GDN1, GDN2, . . . GDNk are 1:1 respectively. Andthus, each garden GDN1, GDN2 . . . GDNK is able to have the working setof resources physically usable from the other gardens exclusively.

(3) Hierarchization of Storage Resources and File System Processing

The data storage processing apparatus 1 of this embodiment executes thehierarchization for the storage 7 (FIG. 2) due to the difference incapacity and/or access speed by hierarchically arranging storageresources of the storage 7 comprising the semiconductor memory 4, thehard disc memory 3 and the magneto-optical disc memory 2B of the autochanger 2 according to capacity and/or access speed.

In practice, the storage having small capacity and high speed like thesemiconductor memory 4 is arranged as the storage to be accessed mostfrequently by the client of the data storage processing apparatus 1 thestorage having medium capacity and medium speed such as the hard disc 3is arranged as the storage to be secondly most frequently accessed, andthe storage with large capacity and low speed like the magneto-opticaldisc memory 2B of the auto changer 2 is arranged as the storage to bethirdly frequently accessed.

With this storage resource hierarchization, the storage structure havinghigh speed and large capacity and efficient cost performance can berealized.

In the case of this data storage processing apparatus 1, hierarchizationaccording to access speed and/or capacity of storage resources isapplied per working set of resources which are divided areas ofresources described above in FIG. 3. Accordingly, the management ofgardens GDN1, GDN2 . . . GDNK which are substances for managing theworking set of resources is executed by the garden manager GDM whichexists uniquely in each garden for its own working set of resources asshown in FIG. 5.

In FIG. 5, in the working set of resources to be managed by each gardenGDN1, GDN2 . . . GDNK, the server file system SFS is introduced tovarious multiple storage resources (the plural number of identicalstorage resources may exist in the same hierarchy) hierarchicallyarranged in the order of the semiconductor memory 4, the hard discmemory 3, the magneto-optical disc memory 2B of the auto changer 2, andthe framework to combine hierarchical storage resources is constructedby one storage manager SGM in each garden GDN. Accordingly, the serverfile system SFS has file management structure proper to this datastorage processing apparatus 1.

The working set of storage resources divided by the server manager SVMis dynamically allocated (i.e., so as to change with time) to the gardenGDN formed by the server manager SVM, and thus the file system can beconstructed on hierarchical various multiple storages to be executed bythe storage manager SGM.

In practice, gardens GDN1, GDN2 . . . GDNK which are dynamicallyallocated the working set of resources hierarchically arranged thestorage resources by designing the way to call out the garden managerGDM of each garden.

More specifically, the garden manager GDM calls out the storage managerSGM, and the called storage manager SGM constructs the server filesystem SFS on the hierarchical storage. The server file system SFS has atree structure including a root a and leaves b, c, d. Nodes e, f, d ofeach file is placed physically in the hierarchical working set ofresources, i.e., divided memory areas of the semiconductor memory 4, thehard disc memory 3 and the magneto-optical disc memory 2B, by thestorage manager SGM as the on-line storage.

Furthermore, the client file system CFS is constructed on the storageheld by the computer of each client, such as personal computer client10, 11, and workstation client 12, and by connecting nodes when occasiondemands, the server file system SFS constructed on the storage 7 held bythe data storage processing apparatus 1 is connected with the clientfile system CFS.

For example, by connecting (hereinafter referred to as mounting) thenode a of the server file system SFS to node g in the client file systemCFS, the server file system SFS can be inputted as a part of client filesystem CFS through the network interface 8 (FIG. 2). This means that thetree structure of files of the client file system CFS has an extendedtree structure inclusive of the tree structure of files held by theserver file system SFS by mounting the node g.

Thus, the client file system CFS is extended to the server file systemSFS, and the user (the client in the client/server model) can access tothe server file system SFS as a part of the client file system CFS.Accordingly, users of this data storage processing apparatus 1 canaccess files in the server file system SFS through the client filesystem CFS without being aware of the physical location of storagewherein files are hierarchically arranged.

As shown in FIG. 5, the tree structure of the server file system SFS isconstructed on the storage 7 (hereinafter referred to as on-linestorage) which is constantly access controlled in a state connected tothe CPU 5. On the other hand, as shown in FIG. 6, the auto changer 2comprising part of the storage 7 has the on-line storage section ONSwhich is constructed by magneto-optical discs as storage media storedinside and the off-line storage section OFS which is constructed bymagneto-optical discs as removable storage media stored outside via theloading/unloading device 2A, and each node of the tree structure of theoff-line storage section ONS is constructed on magneto-optical discsDmo1-Dmo4 which construct the on-line storage section ONS and theoff-line file system OFFS1 and OFFS2 having a similar tree structure tothat of the server file system SFS is constructed on the magneto-opticaldisc composing the off-line storage section OFS.

Nodes j and k of the off-line file system SFFS1 and OFFS2 are connectedto nodes f and d of the server file system SFS respectively, and thus,the off-line file system OFFS1 and OFFS2 function as a part of theserver file system SFS and then as a part of the client file system CFS.As a result, this means that the client file system is expanded.

In the case of FIG. 5, the client file system CFS is constructed on thestorage of client's computer, and a part of nodes of the server filesystem SFS is constructed on the removable media of the magneto-opticaldisc Dmo1-Dmo4 in the on-line storage section ONS (FIG. 6). And, forexample, the node a of the server file system SFS is arranged on themagneto-optical disc Dmo1, and, in the same manner, nodes b and c arearranged on the magneto-optical disc Dmo2, the node f is arranged on themagneto-optical disc Dmo3 and the node d is arranged on themagneto-optical disc Dmo4.

Moreover, the off-line file system OFFS1 to be connected to the node fof the server file system SFS through the node j is constructed on themagneto-optical disc Dmo12 in the off-line storage OFS area. And, in thesame manner, the off-line file system OFFS2 to be connected to node d ofthe server file system SFS through node k is constructed on themagneto-optical disc Dmo11 in the off-line storage OFS area.

In addition to the above construction, two virtual storage media VM1 andVM2 is introduced to the on-line storage ONS. On the on-line storageONS, the first virtual storage media VM1 offers a method to connect themagneto-optical disc Dmo3 on which the node f of the server file systemSFS is arranged and the external magneto-optical disc Dmo11 on which thenode j of the off-line file system OFFS1 is arranged.

Moreover, the second virtual storage media VM2 offers a method on theon-line storage section ONS to connect the magneto-optical disc Dmo4 onwhich node d of the server file system SFS is arranged and the outsidemagnetic memory Dmo12 on which node k of the off-line file system OFFS1is arranged.

These virtual storage media VM1 and VM2 do not really exist on theon-line storage ONS as the magneto-optical disc but are arranged in thestorage media on the on-line storage ONS, such as the corresponding areain the working set of the hard disc memory 3, and controlled by thestorage managers SGN (FIG. 4) arranged in the corresponding gardens GDNk(k=1-K) respectively.

The directory information (having no file substance) of the off-linefile system OFFS1 constructed on the magneto-optical disc Dmo11 of theoff-line storage section OFS to be connected to the node f on themagneto-optical disc Dmo3 of the on-line storage section ONS is storedas the content of the virtual storage of media VM1. In a similar manner,the directory information (having no file substance) of the off-linefile system OFFS2 constructed on the magneto-optical disc Dmo12 of theoff-line storage section OFS to be connected to the node d on themagneto-optical disc Dmo4 of the on-line storage section ONS is storedin the virtual storage media VM2.

Accordingly, since the directory information of the file systemconstructed on media of the off-line storage section OFS is to bemanaged as virtual storage media on the on-line storage section ONS,file system space can be extended to off-line space from on-line space.Thus, the server file system SFS on the on-line space and the off-linefile system OFFS1 and OFFS2 on the off-line space can be treatedlogically like the file system existing on the on-line storage as awhole. Accordingly, users using this data storage processing apparatus 1can handle the off-line file existing on the off-line storage sectionOFS as if they were the off-line file existing on the on-line storagesection ONS.

Next, the management regarding the storage media on the on-line storagesection ONS wherein the server file system SFS is arranged and theoff-line storage media on the off-line storage section OFS is describedbelow including the client's operation (the client in client/servermodel).

In FIG. 7, client A, client B and client C have magneto-optical discsDmo21, Dmo22, Dmo23, and Dmo24, and Dmo25, Dmo26, respectively, asstorage media of the on-line storage section ONS wherein client filesystems CFS are arranged as shown in FIG. 5 similar to that of theclient of FIG. 6.

Also, clients A and B have the externally stored magneto-optical discsDmo31, and Dmo32, Dmo33, respectively, as storage media of the off-linestorage section OFS wherein off-line file systems OFFS1 and OFFS2 ofFIG. 5 are arranged similar to that of the magneto-optical disc Dmo11and Dmo12 of FIG. 6.

Under such conditions, in the on-line storage section ONS, regarding theclient B, the virtual storage media VM22 remaining as a result ofpulling out the magneto-optical disc Dmo32 in the direction from theon-line storage section ONS to the off-line storage section OFS existsas the information showing pulling-out operation of storage media in thedirection to the off-line storage section OFS, and regarding clients Aand B, virtual storage media VM21 and VM23 exist which are placed inorder to insert the magneto-optical disc Dmo31 and Dmo33 in future inthe direction from the off-line storage section OFS to the on-linestorage section ONS.

Moreover, in the off-line storage section OFFS, regarding clients A andC, virtual media VM31 and VM32 exist which are placed in order to pullout the magneto-optical disc Dmo22 and Dmo25 in the direction from theon-line storage section ONS to the off-line storage section OFFS in thefuture.

In practice, at the time when the client A operates to output themagneto-optical disc Dmo22 as the on-line storage media to the off-lineby pulling it out to the outside, as described above in FIG. 4, thestorage manager SGM of the garden GDNk (k=1-K) presently possessed bythe client A pulls out the directory information of the server filesystem SFS arranged on the on-line magneto-optical disc Dmo22 and writesin, for example the file name as the storage media information (medialabel) written on the magneto-optical disc Dmo22 as well as thedirectory information on the virtual storage media newly formed in theon-line storage section ONS in place of the magneto-optical disc Dmo22.

In addition to the above, connection information between the node f(FIG. 5) arranged in the magneto-optical disc Dmo21 as the on-linestorage media and the node j (FIG. 5) arranged in the on-linemagneto-optical disc Dmo22 is written in the virtual storage mediaformed in the on-line storage section ONS. Then, the on-linemagneto-optical disc Dmo22 is removed from the on-line storage sectionONS by the client A and is managed by the client A as the off-linestorage media of the off-line storage OFS shown as the virtual storagemedia VM₃₁. Regarding the client B, the same condition as those of therelation described above between the virtual storage media VM22 of theon-line storage section ONS and the magneto-optical disc Dmo32 of theoff-line storage section OFS is applied.

As a result, as well as by holding and managing the logical connectionrelation between the server file system SFS arranged on the on-linestorage media and the off-line file system LFFS1 and OFFS2 arranged onthe off-line storage media, the correlation among the on-line media f,the virtual storage media, and the off-line storage media is managed onthe on-line, the on-line storage media and the off-line storage media inthe exhausting direction from on-line to off-line can be managed.

Furthermore, at the time when the client B accesses the file written inthe directory information of the virtual storage media VM23, the storagemanager SGM of the garden GDNk which is presently owned by the client Binvestigates correlation information of the storage media written in thevirtual media VM23. Thus, the magneto-optical disc Dmo33 as the off-linestorage media in which the file substance is stored can be recognizedand can also assign the client B to make the off-line storage mediaDmo33 to the on-line storage media of the on-line storage section ONSbased on the media information (electronic label) written in the virtualstorage media VM23.

At the time when the client B transfers the off-line storage media Dmo33to the on-line storage media condition, the virtual storage media VM23is replaced by the storage media Dmo33 substance, and off-line filesystem OFFS1 and OFFS2 arranged in the storage media Dmo33 exists as apart of the server file system SFS arranged on the on-line storage ONS.Thus, the on-line storage media and off-line storage media management inthe direction of storage media insertion from off-line to on-line can beexecuted.

(4) Automatic Labeling Mechanism

In the case of this embodiment, as shown in FIG. 8, a label printer 13forms an automatic labeling mechanism with the loading/unloading device2A of the auto changer 2.

The auto changer 2, by drive controlling the robotic 26 and themagneto-optical recording/reproducing drive 27 via an internal bus 23,an I/O controller 24 and a bus 25 according to the software modulearranged in a memory 22 by the central processing unit (CPU) 21,constructs the magneto-optical disc memory 2B which writes or readssubstantial information by the robotic 26 and the magneto-opticalrecording/reproducing drive 27 by assigning a plurality ofmagneto-optical discs removably stored in the cartridge 28, and storesor pulls out the magneto-optical disc 30 inserted by the client to themedia inlet/outlet 31 in the cartridge 28 by controlling the robotic 26.

In FIG. 8 each manager's software module described above in FIG. 4 isarranged in the memory 22 and executed by the CPU 21. Also, the serverfile system SFS of FIG. 5 is stored in the magneto-optical disc asremovable storage media in the cartridge 28. The function of thesoftware module and the hardware at the time when the client accesses tothe file system described above in FIG. 5 is hereinafter describedexemplifying the working set of resources owned by the garden GDN, andthe server file system SFS which is constructed on the working set ofresources and off-line file system OFFS1, OFFS2 arranged on the off-linestorage media.

If an access request for node f (FIG. 5) of the server file system SFScomes from the client, the garden manager GDM finds the file requestedby the client from the system management information of the file systemwhich the garden manager holds and manages, and delivers the filemanagement information to the storage manager SGM (FIG. 4).

The storage manager SGM reads the slot number of the cartridge 28allocated to the magneto-optical disc in which said file exists from thefile management information and calls out the corresponding mediamanager MDM. The media manager MDM called out controls to the robotic 26via the I/O controller 24 and bus 25 based on the storage information onthe file storage media, and by transferring the corresponding storagemedia stored in the cartridge 28 to the drive 27, accesses the node frequested by the client.

With this arrangement, the magneto-optical disc memory 2B terminates theaccess function according to the access request from the client.

Then, if the access request of the node k (FIG. 5) in the off-line filesystem OFFS2 comes from the client, the garden manager GDM finds thefile requested by the client from the management information of the filesystem held and managed by the garden manager and delivers the filemanagement information to the storage manager SGM. The storage managerSGM recognizes that the file is arranged on the off-line media from thefile management information. As described above in FIG. 7, these areexecuted by checking the information on the virtual media stored in thememory 22 by the storage manager SGM.

If the off-line storage media in which access requested node k isarranged is the magneto-optical disc Dmo31 of FIG. 7, the storagemanager SGM delivers the media information (electronic label) on thevirtual storage media (VM21) to the garden manager GDM. The gardenmanager GDM informs the storage media information of the electroniclabel to the client. The client finds out the magneto-optical disc Dmo31as corresponding off-line storage media from the off-line storage OFSbased on the storage media information and inserts from the mediainlet-outlet 31 in order to replace it by the virtual storage media VM21of on-line storage section ONS.

Thus, the garden manager GDM updates the management information of themagneto-optical disc Dmo31 managed as the virtual storage media as theon-line storage ONS media having substance. The storage manager SGMcalls out the media manager MDM in order to move the insertedmagneto-optical disc Dmo31 to the vacant slot of the cartridge 28. Themedia manager MDM moves the inserted magneto-optical disc Dmo31 toassigned slot of the cartridge 28. Afterwards, the node k is accessed inthe same procedures as those of the node f described above.

In practice, the label printer is a dot impact printer and is installedinside of the auto changer 2, and by connecting this to the internal bus23 via internal wiring, the label printer 13 can be controlled from theCPU 21 of the auto changer 2.

With this arrangement, labels which can be read easily and isdistinguishable by the user can be automatically posted or printed onthe surface of the magneto-optical disc as newly used removable media bythe program control. By writing the electronic labels as the mediainformation of removable storage media and simultaneously posting labelson the surface of media as visual information, clients can easilyexecute the off-line storage media management and the migration of theoff-line storage media to the on-line storage media can be easily andcertainly performed.

(5) Automatic Adjustment Processing of On-Line and Off-Line Capacity

In FIG. 9, the working sets of resources to be managed by the gardenGDN1 are allocated to the client A, and the storage capacity possessedby the garden GDN1 for the semiconductor memory 4, hard disc memory 3and magneto-optical disc memory 2B which compose the storage resourcesof the on-line storage section ONS, and magneto-optical disc of theexternal storage comprising the off-line storage section OFS can beexpressed as the value corresponding to the intersecting areas ofbelt-shaped area which shows the garden GDN1 and belt-shaped areasshowing the semiconductor memory 4, the hard disc memory 3 and themagneto-optical disc memory 2B and the storage area of the externalstorage.

In FIG. 9, the storage capacity of the memory 4, the hard disc memory 3and the magneto-optical disc memory 2B and the external storage of thegarden GDN1, GDN2 and GDN3 is expressed by the volume of capacitydisplays (QA1, QA2 and QA3, and QA4), (QB1, QB2 and QB3, and QB4) and(QC1, QC2 and QC3, and QC4) respectively.

For example, in regards to the semiconductor memory 4, the ratio of theareas of capacity displays QA1, QB1, QC1 of each garden GDN1, GDN2 andGDN3 respectively are different. This means that capacities of thesemiconductor memory 4 allocated to each garden GDN1, GDN2 and GDN3 asthe working set of resources are not equal. The same applies to thedivision of storage resources of the hard disc memory 3 and themagneto-optical disc memory 2B.

As described above, each garden GDN1, GDN2, GDN3 hierarchically arrangesstorages of the semiconductor memory 4, the hard disc memory 3 and themagneto-optical disc memory 2B in its own resources working setdepending upon access time and storage capacity, and constructs theserver file system described above in FIG. 5 on each hierarchicalstorage resource (QA1, QA2, QA3), (QB1, QB2, QB3), (QC1, QC2, QC3).Also, off-line file systems OFFS1, OFFS2 described above in FIG. 5 isconstructed on the hierarchical storage resources (QA4, QB4, QC4) in theoff-line storage section OFS.

The hierarchization of storages and the construction of file systems isexecuted by the software module composed of the garden manager GDM, thestorage manager SGM and the media manager MDM possessed by each gardenGDN1, GDN2, GDN3. Furthermore, each software module of the gardenmanager GDM, the storage manager SGM, the media manager MDM of eachgarden GDN1, GDN2, GDN3 changes the on-line storage capacities ofhierarchical storage resources (QA1, QA2, QA3), (QB1, QB2, QB3), (QC1,QC2, QC3) in time series. This is done on the basis of the accessfrequency of files and the file size in the server file system SFS byeach client.

Thus, by dynamically changing (as the time elapses) the capacities ofstorage resources QA1, QB1 and QC1 of the semiconductor memory 4,capacities of storage resources QA2, QB2 and QC2 of the hard disc memory3 and capacities of storage resources QA3, QB3 and QC3 of themagneto-optical disc, which are working sets of resources possessed byeach garden GDN1, GDN2 and GDN3 respectively according to the accesscharacteristics of clients' files held by each garden GDN1, GDN2 andGDN3. Thus, resources can be allocated to each client fairly andefficiently.

Furthermore, in the present data storage processing apparatus 1, byautomatically adjusting the on-line storage capacity, resources can befairly and efficiently allocated to each client. In addition, byapplying the on-line and off-line media management as described above inFIG. 7, the on-line storage capacity itself can be dynamicallyincreased. Here, the server file system SFS is arranged on the on-linestorage media, i.e., magneto-optical discs Dmo21-Dmo26, in the on-linestorage section ONS of FIG. 7.

Moreover, the off-line file systems OFFS1, OFFS2 are arranged on theoff-line storage media i.e., magneto-optical disc Dmo31-Dmo33, in theoff-line storage section OFS of FIG. 7. Accordingly, in FIG. 9, serverfile systems SFS are arranged on working sets QA3, QB3, QC3 of storageresources of the magneto-optical disc of the magneto-optical disc memory2B as on-line storage media, and off-line file systems OF OFFS1, OFFS2are arranged on working sets QA4, QB4, QC4 of storage resources of themagneto-optical disc as off-line storage media.

In the on-line and off-line media management described above, the clientexecuted the function to output the on-line media to off-line, however,each software module of the garden manager GDM, the storage manager SGMand the media manager-MDM, possessed by each garden GDN1, GDN2 and GDN3,automatically selects files having low access frequency which areconstructed on capacities QA3, QB3, QC3 of the magneto-optical discmemory 2B of the auto changer 2 and simultaneously makes them ascandidates of off-line file systems OFFS1 and OFFS2.

Then, assigning the client to output the on-line storage media on whichcorresponding file are arranged (e.g, magneto-optical discs Dmo22 andDmo25 of FIG. 7), a slot of the magneto-optical disc memory 2B isreleased. Thus, by automatically migrating the on-line media in whichfiles having low access frequency to the off-line, capacity of theon-line storage can be dynamically increased.

According to the data storage processing apparatus 1 as described above,by expanding file system spaces to the off-line and making the on-lineand off-line media manageable, the off-line files all of which cannot bestored in the on-line storage can be operated on the on-line by theclient. Moreover, by extending the on-line and off-line management leadby the client, the on-line storage capacity can be dynamicallyincreased.

In addition to the above, by holding the adjustability of file systemspaces expanded to the off-line and executing self adjustment of theon-line storage capacity for each garden based on the on-line andoff-line management, files capable of increasing storage capacitypractically without limitation can be offered to each client having saidgarden GDN.

(6) Data Storage Processing Operation

According to the foregoing construction, the data storage processingapparatus 1 performs the data storage processing operation according tothe processing procedure described below.

First of all, CPU 5 of the data storage processing apparatus 1 startsthe initialization in the main routine RTO of FIG. 13 and, at the stepSP1, waits for the arrival of garden information request from any of theclients from the network 9 to the data storage processing apparatus 1.If an affirmative result is obtained at the step SP1, the CPU 5 formsthe garden manager at the step SP2.

At this point, the garden manager executes the managing processingprocedure shown in FIG. 14.

More specifically, after making up a path map table as shown in FIG. 15at the step SP11 of FIG. 14, the garden manager forms the storagemanager of FIG. 4 at the step SP12 and finishes the processing at stepSP13.

This path map table TBL1 is constructed for each file system and hasinformation on each node including the server file system SFS, off-linefile systems OFFS1 and OFFS2, and storage file systems SAFS and SBFSshown in FIG. 5 or FIG. 10, and is stored on the hard disc memory 3. Asshown in FIG. 15(A), file system type is stored on this path map tableTBL1 as the header for entry. As this file system type, there are gardenfile system concerning the present invention and other file system suchas UNIX user file system, etc.

Each entry of the path map table TBL1 is constructed by multiple entrytables showing "ordinary file", "directory" or "mount point" as the filetype, and in the case of entry table for file TBL2, "file" is stored asfile type, while "file name", "storage media number" and "file number"are stored as the other information as shown in FIG. 15(B). On the otherhand, in the case of entry table for directory or mount point TBL3, asshown in FIG. 15(C), "directory" or "mount point", is stored as filetype, while "path name" and "pointer to other path map table" are storedas the other information.

Thus, in the case where the garden manager GDM of garden GDN1 or GDNk ofFIG. 4 is formed, the CPU 5 forms the storage manager at the step SP12.

At this point, the storage manager enters the managing processingroutine RT2 as shown in FIG. 16 and waits for the arrival of accessrequest, and at the time when access request arrives, it judges whetheror not the access request is the mount request at the step SP22.

Then, if an affirmative result is obtained, this means that the mountprocessing to connect to the other file system is necessary for the nodewhich is access requested, and, at this point, the CPU 5 proceeds to themount processing subroutine RT3 and executes the mount processingprocedure as shown in FIG. 17.

In the mount processing subroutine RT3, firstly the CPU 5 specifies thefile system type of the path map table of the object to be mounted(e.g., nodes j, k of off-line file systems OFF1, OFF2) and sets in thefile system at the step SP31. Then at next step SP32, the CPU 5 sets themount point (TBL3) on the file type of the path map table (FIG. 15) andreturns to the storage manager processing routine (FIG. 16) from stepSP33.

On the other hand, if a negative result is obtained at step SP22, thismeans that the access request is not a mount processing but a read orwrite processing and CPU 5 proceeds to the read/write access processingsubroutine RT4.

When the CPU 5 enters the read/write processing subroutine RT4, afterresearching the files (i.e., file system type (FIG. 15(A)) and file typeon files or mount points (FIG. 15(B) or (C)) assigned by the client bythe path map table (FIG. 15) at the step SP41, it executes the cachecheck subroutine RT5.

The cache check subroutine RT5 is the processing to check whether or notthe file data to be stored in the magneto-optical disc memory 2B is readout in the hard disc memory 3 or not. Entering the cache checksubroutine RT5, the CPU 5 judges whether or not the current accessrequest is read access at step SP51. In the case of read access request,the CPU 5 judges whether or not the cache data management list has thequeue at the step SP52.

Here, the cache data management list is stored in the hard disc memory 3and as shown in FIG. 20, has a plurality of cache blocks CB1, CB2 . . .the number of which corresponds to number of all slots of themagneto-optical disc memory 2B, and each cache block CBj (j=1, 2 . . . )contains informations on read or write, cache block number andinformation to the next pointer. This cache data management list ismanaged by means of the LRU (least-recently-used) method, and the blockmost recently accessed is listed up to be connected at the head ofqueue, i.e., the leftmost side block CB1 in FIG. 20.

When an affirmative result is obtained at the step SP52, the CPU 5proceeds to step SP53 and executes the queuing process on the head ofthe read cache management list regarding the discovered queue and readsout the file data of the queuing processed block and returns to theread/write access processing routine RT4 (FIG. 18) from step SP59.

On the other hand, if a negative result is obtained at step SP52, theCPU 5 proceeds to step SP55 and executes the cache mishit processing,and upon storing the cache mishit result in the internal memory 6,proceeds to the step SP54 and finishes the processing.

Furthermore, if a negative result is obtained at step SP51 describedabove, this means that the present access request is the write mode, andthe CPU 5 proceeds to the step SP56 and writes the file data to bestored in the storage 7 in the hard disc memory 3 for a while and storesthat the access request is write access request in the internal memory 6and proceeds to step SP54 described above and finishes the processing.

With this arrangement, when the cache check processing is finished, theCPU 5 returns to the read/write access processing subroutine RT4 (FIG.18) and judges whether or not the caching is finished at the step SP42.

At this point, if an affirmative result is obtained, the CPU returns tothe storage managing processing routine (FIG. 16) from step SP43. On theother hand, if a negative result is obtained at step SP42, the CPU 5proceeds to the step SP44 and judges whether the access request arrivedat step SP21 (FIG. 16) is the file data to be managed by the garden filesystem (GFS) referring to file system type of the path map table (FIG.15), and, if an affirmative result is obtained, enters the garden filesystem processing routine RT6.

On entering the garden file system processing routine RT6, the CPU 5judges whether the disc is accessed for the first time or not at stepSP61 as shown in FIG. 21, and, if an affirmative result is obtained, theCPU 5 forms the media manager of FIG. 4 at the step SP62 and returns tothe read/write access processing routine RT4 (FIG. 18) from step SP63.

At this point, after executing the reading processing of the mediaaccess management table (FIG. 26) at step SP71 as shown in FIG. 22, theCPU 5 judges that the media manager is off-line or not at the step SP72,and, if an affirmative result is obtained, the CPU 5 returns to stepSP71 described above after processing the off-line processing subroutineRT8.

Here, the CPU 5 judges whether, in the media numbers stored in the mediaaccess management table TBL31, the media number which coincides with themedia number of the magneto-optical disc on which the file to beaccessed is stored exists. In this connection, the media number of themagneto-optical disc on which the file to be accessed is stored can befound from the storage media number in the file type storage informationof the path map table TBL1.

Moreover, when the CPU 5 enters the off-line processing subroutine RT8,it executes the processing to output the media label of the intra-mediamanagement table TBL11 (FIG. 24) to the client at step SP81 as shown inFIG. 23.

The intra-media management table TBL11 is installed in each storagemedia (i.e., magneto-optical disc 2B), and this table TBL11 contains themanagement information on "media label", "file number" and "nodepointer" of files stored in the storage media as shown in FIG. 24(A).

The node table TBL12 shown in FIG. 24(B) is stored on the position shownby the node pointer of each file number of the intra-media managementtable TBL11 of each storage media and, thus, informations on "owner","permission", "access time", "time changed", "single block pointer"(contains data which is the file substance as shown in FIG. 24(C)),"double block pointer" (contains a block pointer and the correspondingfile substance data as shown in FIG. 24(C)), and "triple pointer"(contains 2 block pointers information and file data as shown in FIG.24(C)) are stored.

Then, the CPU 5, upon outputting the media label at step SP81 (FIG. 23),waits for the user to insert the designated medium to theloading/unloading device 2A of the auto changer 2 at the next step SP82,and, when the CPU 5 confirms that the insertion has been done, returnsto step SP71 of the media manager processing routine RT7 (FIG. 22) viastep SP83. Here, the user can distinguish the targeted storage medium bythe labels posted on the media.

If a negative result is obtained at step SP72 of the media managerprocessing routine RT7 (FIG. 22), this means that file access requestedis not off-line, but is on-line (the media is inserted in the slot),and, the CPU 5 proceeds to step SP73 and after reading in the i-nodeassigned by the i-node pointer from the file number of the intra-mediamanagement table (FIG. 24), judges whether the read command is necessaryat the step SP74.

If an affirmative result is obtained at the step SP74, the CPU 5executes the processing of read cache processing routine RT9.

When entering the read cache processing routine RT9, the CPU 5 executesthe processing to remove the blocks connected to the last queue of thecache data management list on the plural number of blocks as needed atstep SP91, and then, at the step SP92, the CPU 5 executes the processingto read out the file data from the block assigned by the block pointerof the i-node table (read ahead) and, at step SP93, the CPU 5 processesto connect the queue including the file data now read in the cache datamanagement list to the head of queue, and then, at the following stepSP94, after executing the update processing of the access count data andstaging information of the media access management table TBL31 (FIG.26), the CPU 5 returns to the media manager subroutine RT7 (FIG. 22) viastep SP95.

Here, as shown in FIG. 26, the media access management table TBL31stores "access count" (access history, i.e., it shows the number ofaccess), "staging information" (e.g., information to show access time)and "media lock/unlock information" in every slot number as the wholestorage, and, the CPU 5 executes the updating processing at step SP94 inutilizing the stating information and the access count information.

If a negative result is obtained at step SP74 of the media managersubroutine RT7 (FIG. 22), this means that the current request is not aread command but rather, a write command, and, at this moment, the CPU 5executes the following write cache processing subroutine RT10.

When entering the write cache subroutine RT10, the CPU 5 executes theprocessing to remove the block (a plurality of blocks as necessary)connected to the last queue of the cache data management list (FIG. 20)as shown in FIG. 27, and, at the next write preparation routine RT11,the CPU 5 prepares for the writing process of file data to the blockspecified by the block pointer of the i-node table TBL12 (FIG. 24(B)) ofthe file.

When the CPU 5 enters this write preparation processing routine RT11, itjudges whether vacant space exists in the media to be assigned at stepSP111 as shown in FIG. 28.

This judgment is to confirm whether the file data to be written can bewritten in the magneto-optical disc because of the space remaining inthe assigned media, i.e., the magneto-optical disc, and the degree ofremaining space will be known using the data stored in every slot numberas the remaining capacity data of the media access management tableTBL31 (FIG. 26).

If an affirmative result is obtained at step SP111, meaning that thereremains enough room for the file data to be written in themagneto-optical disc by the current access request without anyomissions, the CPU 5 proceeds to step SP112 and updates thecorresponding node table TBL12 in the intra-media management table (FIG.24), and after updating the entry table TBL2 or TBL3 of the path maptable TBL1, returns to the write cache processing routine RT10 (FIG. 27)at step SP113.

On the other hand, if a negative result is obtained at step SP111meaning that there is no room for the information data to which accessis requested in the assigned storage medium, i.e., the magneto-opticaldisc, the CPU 5 proceeds to step SP114 and judges if there exist anyvacant media in the magneto-optical disc memory 2B in the auto changer.

At this step SP114, the CPU 5 executes the processing to search slotshaving large remaining capacity and to which the garden is notallocated. (the slot number which does not exist as the garden number).

If an affirmative result is obtained at step SP114, meaning that avacant media is found in the auto changer 2, the CPU 5 proceeds to stepSP115, and after executing the processing to tabulate the information onthe storage media into a management table in the intra-media managementtable TBL11 (FIG. 24), updates the node table of the intra-mediamanagement table TBL11 (FIG. 24) at step SP116 and simultaneously, itupdates the entry table TBL2 or TBL3 of the path map table TBL1, andthus, the CPU 5 finishes the preparation to write the information datato which access is requested for the vacant media in the auto changer 2.

Accordingly, at this point, the CPU 5 returns to the write cacheprocessing routine RT10 (FIG. 27) via step SP113.

Furthermore, if a negative result is obtained at step SP114, this meansthat there is no vacant storage media in the auto changer 2, and at thispoint, the CPU 5 proceeds to step SP117 and judges whether there is roomin the media access management table TBL31 or not.

The judgment at this step SP117 is to execute the processing to searchwhether there are any slot numbers on which no data is stored on themedia number columns in the media access management table TBL31 (FIG.26), and when an affirmative result is obtained, it means that thereexist slots in which no storage media, i.e., no magneto-optical disc, isinserted are discovered, and, at this point, the CPU 5 proceeds to stepSP118 and, after outputting the information to show that the vacantmedia, i.e, the magneto-optical disc on which no information is writtenis inserted to the slot of the slot number to the client via the networkinterface 8, the CPU 5 waits for a new magneto-optical disc to beinserted at step SP119.

Then, when an affirmative result is obtained at step SP119, the CPU 5can confirm that the user inserted a new storage medium, and whileupdating the node table TBL12 of the intra-media management table TBL11and updating the entry table TBL12 or TBL13 of the path map table TBL1at step SP116, and returns to the write cache processing routine RT10(FIG. 27) from step SP113.

On the other hand, if a negative result is obtained at step SP117, thismeans that there exists no vacant storage media in the auto changer, andat this point, by executing the media discharging processing routineRT12, the CPU 5 executes the media discharging processing to pull outsome of the magneto-optical discs in the auto changer 2, and thus, theprocessing to make vacant slots in the auto changer 2 is performed.Then, the CPU 5 executes the processing to return to the write cacheprocessing routine RT10 (FIG. 27) via steps SP118, SP119, SP116 andSP113.

On entering in the media discharging processing subroutine RT12, the CPU5 selects the least frequently accessed storage medium (that is theleast frequently used storage medium) from the media access count andthe staging information in the media access management table TBL (FIG.26) at step SP121 and then judges whether the storage medium is lockedor not at step SP122.

At this point, if an affirmative result is obtained, this means that theleast frequently accessed storage medium is locked up so that thismedium cannot be changed to off-line freely, and at this moment, the CPU5 returns to step SP121 described above, and after selecting the secondleast frequently accessed storage medium, executes the processing ofstep SP122 on the storage medium.

If a negative result is obtained at step SP122, this means that theselected storage media can be discharged, and at this moment, the CPU 5proceeds to step SP123 and checks the cache data management list (FIG.20), and after executing the file data flushing on the storage media,executes the discharge/print processing from the next step SP124.

At this point, if the read/write data of the cache block connected tothe end of list is write, the CPU 5 executes the flush processing towrite the file data of the cache block stored in the hard disc to thecorresponding storage medium of the magneto-optical disc memory.

At step SP124, the CPU 5 judges whether the media label has already beenwritten in the storage medium with the corresponding slot number in theintra-media management table TBL11 (FIG. 24) or not, and if a negativeresult is obtained, the CPU 5 forms media label at step SP125 and printsthe media label at the label printer 13 (FIG. 2) through the printer I/Fat step SP126. Thus, the client, by putting this label on the cartridgeof the magneto-optical disc, can distinguish this magneto-optical discfrom the other discs even though this magneto-optical disc changes tooff-line. Then, the CPU 5 sets the media label on the media label fieldof the intra-media management table TBL11 (FIG. 24) at step SP127, andit finishes the media discharge processing subroutine RT12 (FIG. 29) viastep SP128.

On the other hand, if an affirmative result is obtained at step SP124described above, this means that the media label has already beenwritten and the new setting is unnecessary, i.e., the label has alreadybeen pasted on the cartridge of the magneto-optical disc. At this point,the CPU 5 returns to the write preparation processing routine RT11 (FIG.28) skipping over steps SP125-SP127.

With this arrangement the discharging preparation of and discharging themagneto-optical disc to the outside as well as the automatic labeling isexecuted. Then, the CPU 5 finishes the write preparation processingroutine RT11 passing through steps SP118, SP119, SP116 and SP113 andreturns to the write cache processing routine RT10 (FIG. 27). At stepSP102, the CPU 5 allocates cache block from the cache data managementlist on the data to which write process is requested and connects thisto the head of the queue. At the next step SP103, the CPU 5 updates thestaging information of the media access management table TBL31 (FIG. 26)so as to finish the write cache processing subroutine RT10. And the CPU5 returns to the media manager forming processing subroutine RT7 (FIG.22) from step SP104 and finishes the garden file system (GFS) processingroutine RT6 (FIG. 21) via step SP75. Thereby, the CPU 5 returns to theread/write access processing routine RT4.

On the other hand, when a negative result is obtained at step SP61 ofthe garden file system (GFS) processing routine RT6 (FIG. 21), the CPU 5judges that access to the disc is not for the first time and returns tothe read/write access processing routine RT4 (FIG. 18) from step SP63skipping over the media manager forming step. Thereby, the CPU 5 returnsto the storage manager processing routine RT2 (FIG. 16) from step SP43.

In the case described above, the operation of CPU 5 when the garden filesystem (GFS) is placed on the storage 7. However, in the case of placingother files on the storage 7 with the garden file system (GFS), anegative result can be obtained at step SP44 of the read/write accessprocessing subroutine RT4 (FIG. 18). Thus, the CPU 5 judges that thefile to which access is requested is the file in the file system otherthan the garden file system and then enters to the other file systemprocessing subroutine RT14.

Thus, on entering in the other file system processing subroutine RT14,the CPU 5 changes the path name of the file system of the garden filesystem (GFS) path map table TBL1 at step SP141 as shown in FIG. 30.Then, the CPU 5 starts the file system handler at step SP142, proceedsto step SP143 and judges whether the file to which access is requestedis for the off-line or not on the basis of the media access managementtable TBL31.

At this point, if an affirmative result is obtained, this means that theoff-line processing is necessary at the moment. Then, the CPU 5 entersthe off-line processing subroutine RT8 and executes the off-lineprocessing RT8 described above in FIG. 23, then returns to step SP142.

On the other hand, if a negative result is obtained at step SP143, thismeans that the on-line processing is necessary. Then, the CPU 5 returnsto the read/write access processing subroutine RT4 (FIG. 18) from stepSP144.

At this point, the CPU 5 finishes all processings of the read/writeaccess processing subroutine RT4 and returns to the storage managerprocessing (FIG. 16) via step SP43. Then, the CPU 5 waits for arrivingnew access request at step SP21.

Accordingly, the CPU 5 can execute the operation described above in FIG.1-FIG. 12 according to the processing procedure described above in FIG.13-FIG. 30.

(7) Other Embodiments

(7-1) FIG. 10 shows another embodiment according to the presentinvention. In this case, by mounting node h of the storage A file systemSAFS constructed on the storage comprising the write once type opticaldisc memory to node b of the server file system SFS, the data storageprocessing apparatus 1 treats files in the storage A file system SAFS asa part of the server file system SFS.

Furthermore, by mounting node i of the storage B file system SBFSconstructed on the storage comprising the optical disc memory to node cof the server file system SFS, files in the storage B file system SBFScan be treated as a part of the server file system SFS.

In the case of the data storage processing apparatus 1 constructed as inFIG. 10, since the file system constructed on the other storage, i.e.,the storage comprising write once type disc memory, optical disc memory,in addition to the magneto-optical disc memory storage, can be mounted,the user can access the optional file systems constructed on varioustypes of storages through the client file system CFS without being awareof the storage. More specifically, the storage manager SGM to be calledby the garden manager GDM executes the mounting of the file systemhaving the other file management structure including server file systemSFS and client file system CFS to nodes b, c, d, f of the tree structurein the server file system SFS.

Since the storage manager SGM has the module which understands the filesystem structure to be mounted, various multiple file systemsconstructed on various multiple storages can be mounted in the serverfile system SFS, and also the file system mounted can be treated as anextension of the server file system SFS.

For example, the storage A file system SAFS is constructed on thestorage like the write once type optical disc, and by mounting node h ofthe storage A file system SAFS to node b in the server file system SFS,files in the storage A file system SAFS can be treated as a part of theserver file system SFS. In the same manner, by mounting node i of thestorage B file system SBFS to node c in the server file system SFS, thestorage B file system SBFS constructed on the storage like the opticaldisc can be treated as an extension of the server file system SFS.

Thus, according to the data storage processing apparatus 1, variousmultiple file systems constructed on various multiple storages can bemounted together, and moreover, the client can access files in variousmultiple file systems, such as the server file system SFS, storage Afile system SAFS and storage B file system SBFS as extensions of theserver file system SFS through the client file system CFS without beingaware of storages.

(7-2) FIG. 11 shows another embodiment of the present invention. Thedata storage processing apparatus shown in FIG. 11 hierarchicallyarranges from the client storage CLS to the off-line storage OFSaccording to access speed of the storage. This is equivalent to FIG. 9,but here each storage is treated as a cache. The client storage CLSclosest to the client (the storage having the fastest access speed tothe client) is called the primary cache, and in the order of decreasingaccess speed, the semiconductor memory 4 is called the secondary cache,the hard disc memory 3 is the tertiary cache and the magneto-opticaldisc memory 2B of auto changer 2 is called the quartic cache. This isthe way of thinking equivalent to those of the primary cache andsecondary cache for the main storage memory (semiconductor memory) ofthe micro-processor but extended to storages including off-line.

According to the foregoing construction, files in the file systems areaccessed by the client who constructed the file systems, such as theserver file system SFS, off-line file systems OFFS1, OFFS2 on thehierarchical storages. However, in the case of FIG. 11, files areautomatically migrated by the storage manager SGM which each garden GDNhas only one, being staged in the high speed cache, such as the clientstorage CLS and the semiconductor memory 4 (finally staged in theprimary cache), or being staged in the low speed cache such as the autochanger 2 (finally staged in the off-line storage OFS). Thus, the accessperformance of the file to be frequently accessed will be improved, andhierarchical storages can be effectively utilized.

Furthermore, in the data storage processing apparatus 1, files in theserver file system SFS which are accessed by the client, is arranged onthe magneto-optical disc memory 2B of the auto changer 2 and these fileswill migrate by the staging between caches according to the accessfrequency of the files as the time passes. However, gathering of thestatistical data, such as access frequency of the file by the client,and their lives on the storage and cache, is executed by the storagemanager SGM.

Thus, the user of this data storage processing apparatus 1 can analyzethe operating condition of the data storage processing apparatus 1 andthe utilization condition of resources of the data storage processingapparatus 1 which is used in the application. Furthermore, as a resultof the statistical data analysis by the user, distributions ofapplications and resources of the data storage processing apparatus 1,and the processing speed tuning can be executed.

In addition to the above, the garden manager GDM which each garden GDNhas only one, manages the statistical data in the data storageprocessing apparatus 1, and by applying the on-line and off-line mediamanagement, useless files having very low access frequency formed by theuser on the on-line storage can be automatically removed as off-linefiles, and the on-line media on which the files are arranged can beoutputted to off-line according to the procedure described above.

As shown in FIG. 12, the processing for removing the off-line file canbe done by executing the slot management for the magneto-optical disc asa removable storage in the auto changer 2. FIG. 12 shows capacities ofthe magneto-optical disc memory 2B in storage resources QA3, QB3, QC3 ofeach garden GDN1, GDN2, GDN3 of FIG. 9 (having capacities according tothe number of slots in the cartridge 28 (FIG. 8)).

At present, clients A, B and C which have gardens GDN1, GDN2 and GDN3have slots (SL1, SL2), (SL3-SL6) and (SL7-SL9) respectively, andmagneto-optical discs are inserted in all slots as removable storagemedia. For explanation, let it be supposed that the maximum number ofslots of the auto changer 2 having the magneto-optical disc memory 2B is8 slots SL1-SL8 and no vacant slot exists at present.

By applying the automatic adjustment of the on-line capacities based onthe statistical data described above, the garden manager GDM having theon-line media in which the server file system SFS with low accessfrequency is placed is called out by the server manager SVM for theclient C's access request to the off-line storage media, i.e.,magneto-optical disc Dmo42, and the on-line media is automaticallymigrated to the off-line media.

For example, the magneto-optical disc as a storage media possessed bythe client A's garden GDN1 in the slot SL2 is outputted as the off-linestorage media Dmo41. Thus, the off-line storage media Dmo42 can bemigrated to the client C's garden GDN3 on-line and can be functioned asthe on-line storage media of slot SL9. At this point, the client A'sgarden GDN1 dynamically changes to have one slot SL1 and the client C'sgarden GDN3 dynamically changes to have three slots SL7, SL8, SL9.

Accordingly, by dynamically changing the number of slots of the autochanger 2 of the magneto-optical disc that can be possessed by thegarden GDN1, GDN3 of the client A, C corresponding to the accessfrequency and file size of the client's file, the client's files to befrequently accessed can be kept in on-line.

Furthermore, according to this embodiment, slots of the auto changer 2of the magneto-optical disc possessed by gardens GDN1, GDN3 of clientsA, C are dynamically changed. However, this does not apply to slotsowned by the client B's garden GDN2. These slots are allocated to theclient B's garden GDN2 as slots for exclusive use for the garden GDN2 bythe user.

The magneto-optical disc as removable storage media is inserted in slotsSL3 and SL4 of the client B's garden GDN2, but no removable media isinserted to slots SL5 and SL6, i.e., vacant condition. Under thesecircumstances, slots SL5 and SL6 will not be allocated to other clientsA's, C's gardens GDN1, GDN3, but the client B's garden GDN2 canexclusively possess slots SL5, SL6. Thus, the client B can use slots SL5and SL6 exclusively regardless of access frequency of files as occasiondemands.

(7-3) The embodiment described above has dealt with the case of the datastorage processing apparatus 1 wherein the magneto-optical disc memory2B comprising the semiconductor memory 4, the hard disc memory 3 and theloading/unloading device 2A as the storage is hierarchized according toaccess speed and storage capacity as the hierarchization condition.However, the storage and hierarchization condition is not only limitedto the above but also the write once and read many times write once typeoptical disc, read only optical disc, sequentially accessible tapestreamer, etc. may be applied as storage and the hierarchization may beexecuted according to feature and characteristics of the storageapplied.

(8) Advantages of the Embodiment

According to the foregoing construction, since the storages inclusive ofoff-line storage media can be offered as the storages by building up thedevice construction having storage hierarchization including off-linestorages which cannot be accessed on-line and the management system ofstorages and files which can be obtained by the software includingoff-line, the data storage processing apparatus capable of improving theusability of users and expanding its storage capacity practicallywithout limitation can be obtained and unfairness among users can beremoved.

Furthermore, according to the foregoing construction, by arranging thehard disc 6 to the auto changer 2 of magneto-optical disc as a cache,files to be used frequently are automatically staged in the hard disc 6and files can be read or written by the performance of the hard disc 6.Also, files on the removable media on the off-line can be treated as ifthey were on-line files on the server by the file media managementincluding off-line media.

Furthermore, according to the foregoing construction, at the time whenthe client accesses the file which does not exist on the on-line, thesystem can inform the client to insert the off-line media wherein thefile exists. Moreover, at the time when new removable media is inserted,by automatically writing media information comprising electronic labelsand posting visually recognizable labels on the media, users can controlthe off-line media more easily and certainly and simultaneously, cantransfer the off-line media to on-line.

Moreover, according to the foregoing construction, by automaticallyoutputting files having low access frequency to off-line, the on-linestorage capacity can be increased to 3-10 times. Besides, the client'suseless files can be automatically rearranged. Furthermore, thedirectory in the off-line media outputted automatically to off-line iscontrolled as the virtual media on the on-line and can be migrated tothe on-line on demand. Also, files having practically indefinite largecapacity can be realized by controlling the file media includingoff-line media and effective utilization management of the on-linestorage capacity.

Furthermore, according to the foregoing construction, various multiplestorages can be easily mounted and the file system possessed by eachstorage can be mounted in the internal file system of its own. Thus, theclient can access various file systems which he has in each storage ashis own internal file system.

Furthermore, according to the foregoing construction, by collectingstatistical information on access frequency, the present storagelocation and cache life length of clients' files, users can analyze theoperating condition of the server and the utilization condition of theserver source. And the application and server performance tuning can beexecuted depending on the analysis result.

Moreover, according to the foregoing construction, since the systemautomatically secures and releases the number of slots of the autochanger of the magneto-optical disc which is allocated to each clientcorresponding to the access frequency and size of the file, the on-linecapacity of each client can be automatically adjusted and the client'sfile to be accessed frequently can be remained in on-line. Also, sinceslots are locked by the client for his exclusive use, the client canexclusively use them with the specific application regardless of fileaccess frequency. Besides, the client can commonly use them with theother clients who share the same application such as a database.

Industrial Applicability

The data storage processing apparatus according to the present inventioncan be utilized by a variety of clients who require large capacitystorage device, and can be utilized for the accumulation of electronicpublishing data, stock data and catalog publishing data.

Moreover, the data storage processing apparatus according to the presentinvention can be utilized for the document image processing, such aspreservation of attested copy of government document and preservation ofdrawings on patents.

Furthermore, the data storage processing apparatus according to thepresent invention can be used for the game software developing business.

I claim:
 1. A data storage processing apparatus comprising:storing meansfor storing multiple path map information; accessing means for accessingstorage media; controlling means for controlling said storing means andsaid accessing means based on command; and said path map informationcomprising, file system information indicating the type of file systems;file type information stored as a plurality of entries with respect tosaid file system information to identify a file and a directory to beaccessed under the file system shown by said file system information anda mounting point indicating switching point to other file system; andpointer information indicating the storage position of path mapinformation with respect to said other file systems in the case saidfile type information is said mount point; and wherein said controllingmeans operates under first file system according to inputted commanddepending on first file system information and detects file to whichaccess is requested by said command from said path map information, andreads out other path map information based on said pointer information,and controls to access a file to which access is requested under filesystem indicated by file system information contained in the other pathmap information which has been read out.